A) Field of the Invention
The present invention relates to a music data distribution system, and more particularly to a music data distribution system for converting music data and distributing the converted music data to an external device via a network.
B) Description of the Related Art
There is a music data distribution system wherein music data of a musical instrument digital interface (MIDI) format, an MPEG Layer 3 (MP3) format or the like capable of being reproduced by electronic musical instruments, computers and the like can be purchased by downloading from a server via a network such as the Internet, instead of purchasing music data recorded in a recording medium such as a CD-ROM at stores.
In such a data distribution system, the music data is likely to be prepared in only one quality. Therefore, a user who just needs a low quality data sometimes needs to buy a high quality data for an expensive price.
The quality of music data includes not only the sound quality of reproduced music, but also the amount of information contained in the music data. The information contained in the music data includes score data corresponding to the music data, data for controlling a tone generator, and the like. In this specification, music data containing a larger amount of information is called music data of a high quality or high quality music data.
Music data is often sold separately for mobile phones and electronic musical instruments. Generally, music data for mobile phones and electronic musical instruments is recorded in different file formats, so that one cannot reproduce music data for another.
Therefore, the user should purchase music data that can be reproduced by an apparatus owned by the user. The user is required to search reproducible music data from a large amount of music data. It is also necessary for each user apparatus to access in a manner specific to the apparatus a home page selling reproducible music data.
If music data of various file formats and qualities compatible with various types of apparatuses is to be sold at one home page, a number of files are required to be prepared for each music piece and the memory capacity of the server increases.
If the number of types (qualities and file formats) of music data to be dealt with one home page increases, it becomes more difficult to select reproducible music data by using an apparatus owned by a user, leaving a risk of diminishing purchase desire.